1. Technical Field
The present invention relates to print controllers for bidirectionally communicating with printers.
2. Related Art
A terminal running under Windows (Registered Trademark) has a bidirectional (BiDi) communication function for bidirectionally communicating with a device such as a printer. The use of the bidirectional communication function allows the terminal to transmit a command to the printer and to acquire response data corresponding to the transmitted command from the printer.
In a Version 4 printer driver (hereinafter also referred to as a V4 printer driver) running under Windows 8 and subsequent versions, the bidirectional communication function is defined as an extended function for device control. According to the extended function, the process of transmitting a command from an application to a printer and the process of acquiring response data from the printer are realized by separate interfaces written in JavaScript (Registered Trademark). For example, in order to transmit the command issued by the application to the printer, a series of processes is performed by using a set method of the extended function. On the other hand, to acquire the response data from the printer, a series of processes is performed by using a get method of the extended function.
An example of the related art is found at http://msdn.microsoft.com/library/windows/hardware/br259124.
According to the bidirectional communication function of the V4 printer driver, the processes performed by using the set method are not synchronized with the processes performed by using the get method. Therefore, there is a case where a command transmitted by using the set method does not correspond to data acquired by using the get method.